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~('JO~77 Yampa River Basin. The Section 7 Baseline flows reflected a scenario which included a future Ievel of deveIopment with all proposed projects likeIy to be developed, including the Stagecoach Reservoir Project. When the Recovery Implementation Program Recovery Implementation Plan (RIPRAP) was formed, the need to update the Yampa River flow recommendations was recognized, Since 1990, the USFWS has been working with the Colorado River Water Conservation District, Bureau of Reclamation, Colorado Water Conservation Board and The Nature Conservancy on the Yampa River Basin Alternatives Feasibility Study and the Yampa River Basin Recommended Development Alternative - Detailed Feasibility Study. During these studies, a great deal of new data have been developed on depIetions and reservoir operations in the Yampa River Basin. This new information has been used as the basis for updating the flow recommendations as prescribed in the RIPRAP. The updated flow recommendations replace the March, 1990 recommendations and represent the USFWS recommendations for water rights acquisition and flow protection to heIp recovery of the endangered fish ofthe Yampa River Basin. Deviations from the recommendations does not mean that a project will receive a jeopardy opinion with no reasonable and prudent aIternative. Updated Flow Recommendations Updated flow recommendations were developed for the Yampa River at Mayben and at Deerlodge Park. The recommendations at Mayben are based on the results of a modeled baseline scenario (further discussed below) developed during the Yampa River Basin Recommended Development AIternative - Detailed Feasibility Study. The updated flow recommendations for the Yampa River at Mayben are presented in TabIe 2. TabIe 2 u.s. Fish and Wildlife Service Updated Flow Recommendations at Mayben Month Recommended Flow (cfs) 204 (50% exc,) 255 (50% exc,) 228 (50% exc.) 217 (50% exc.) 256 (50% exc.) 498 (50% exc.) * * * 999 (50% exc,) 220 (50% exc.) 91 ** (50% exc,) October November December January February March April May June JuIy August September * Percentile which occurs naturally in any given year. ** The 50% exceedance flow for September is based on water availability considerations associated with the assumptions in the Yampa River Basin Model. The USFWS recognizes that the conditions modeled are based on ~orst case assumptions and that flows are not likely to drop to this level in the near future. If this flow level were to regularly occur there may be a need to secure augmentation sources to maintain or enhance late summer flows. 13